• Journal of Oral Medicine and Pain
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• v.9 no.1
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• pp.103-116
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• 1984

Randumly sampled out 157 extracted Korean adult teeth, aged 12 to 79 years, was applicated to estimat the age by Gustafson's method, were evaluated and analyzed in terms of phyological aging change. The results are as follows : 1. It was reconfirmed that there existed comparatively close correlationship between age and score, especially in old age. 2. Korean score had comparatively high level than those of European. 3. In the probability of age edetermination, the estimation error was the most high level in the age of 70~ with ±4.47, and next order was in the age of 10-19 with ±5.20,60-69 with ±5.8,30-39 with ±5.98,50-59 ±6.20,40-49 with ±6.72,20-29 with ±9.28.Mean value was ±8.03. 4. The regression equation is as follows. y=3.55x+8.52(r=8.75) standard deviation σ=±8.03 (y= estimated age x=score) 5. In age determination with those data, needs to estimate slightly lower than caculated age in range of 10-49, and higher in 50-70 for the real age determination.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.449-451
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• 2007

In the commercially managed timber lands, the information such as height, age, stand density, canopy closure and leaf area index need to be collected periodically. Stand volume is the most fundamental information in the valuation of timber, however, stand age information is the primary element of forest inventory and these two are highly correlated. Conventional method of collecting stand age information by field surveys such as ring count method is accurate; however, it is expensive, labor-intensive and time consuming. In the present study it was aimed to collect stand age information using modem techniques in a commercially managed timberland situated in Tennessee, USA. The Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+) of three different periods, Shuttle Radar Topography Mission (SRTM), National elevation dataset (NED) and field inventory data were used. Normalized difference vegetation index (NDVI) and Tasselled Cap (TC) transformation techniques were applied on the TM and ETM+ data. The regression analysis was carried out to identify the correlation between stand age and NDVI, TC. In the present study about 2,469 datasets were analyzed. The $R^{2}$ value for stand age estimation was 0.713. The NDVI, TC2 and TC3 were found to produce accurate timber age information.

• Advances in nano research
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• v.12 no.2
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• pp.197-212
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• 2022

The purpose of this study is to develop an automatic software system for bone age evaluation and to evaluate its accuracy in testing and feasibility in clinical practice. 20394 left-hand radiographs of healthy children (2-18 years old) were collected from China Skeletal Development Survey data of 1998 and China Skeletal Development Survey data of 2005. Three experienced radiologists and China-05 standard maker jointly evaluate the stages of bone development and the reference bone age was determined by consensus. 1020 from 20394 radiographs were picked randomly as test set and the remaining 19374 radiographs as training set and validation set. Accuracy of the automatic software system for bone age assessment is evaluated in test set and two clinical test sets. Compared with the reference standard, the automatic software system based on RUS-CHN for bone age assessment has a 0.04 years old mean difference, ±0.40 years old in 95% confidence interval by single reading, a 85.6% percentage agreement of ratings, a 93.7% bone age accuracy rate, 0.17 years old of MAD, 0.29 years old of RMS; Compared with the reference standard, the automatic software system based on TW3-C RUS has a 0.04 years old mean difference, a ±0.38 years old in 95% confidence interval by single reading, a 90.9% percentage agreement of ratings, a 93.2% bone age accuracy rate, a 0.16 years of MAD, and a 0.28 years of RMS. Automatic software system, AI-China-05 showed reliably accuracy in bone age estimation and steady determination in different clinical test sets.

• The Journal of the Korean dental association
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• v.19 no.5 s.144
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• pp.439-448
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• 1981

• Phonetics and Speech Sciences
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• v.6 no.2
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• pp.81-88
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• 2014

The normal aging process on speech production and these changes are perceived by listeners. This study examined whether age perception changed under various conditions of prosodic manipulations in normal listeners, comparing the prosodic changes according to age and sex in adulthood. The older and younger voices were resynthesized by manipulation of the speaking rate and pitch to shift the perceived age of the groups toward each other. Two-way repeated ANOVA were conducted to determine if the prosodic type of resynthesized cue resulted in a significant shift in perceived age of young and old voices. The manipulation of the speaking rate resulted in a significant shift in perceived age for the older and younger groups. A significant shift in age estimates was not observed for the younger male group when pitch was manipulated. There were significant gender-by-age group interactions for prosodic manipulation type. Age-related changes in the prosodic properties of speech may ultimately influence speech perception.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.176-189
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• 2017

Age estimation and sexual dimorphism of Coreoleuciscus splendidus were estimated using otolith, length-frequency distribution and 23 morphological measurements, from 245 individuals collected from September 2016, February and April 2017 in the Gapyeong stream, Han River, Korea. Result of age estimation of C. splendidus, we most examined were 2, 3 and 4-age, and the maximum observed ages were 5-age. Nine out of twenty-three morphometric measurements were significantly different between the genders. Anal fin have showing major sexual dimorphism in particular between adult individuals. This sexual dimorphism was based on extension of anal fin soft rays of male individuals. Therefore anal fin of males is always longer and wider than females. During spawning season male individuals possess nuptial tubercles on anal fin rays. However, another measurements and morphological characters does not exhibit sexual dimorphism in the between male and female individuals. The sexual dimorphism was observed to only over 2-years old individuals with sexual maturity. But juvenile and 1-years old individuals do not have sexual dimorphism with sexual maturity. Peak season of spawning was April to May and they start first spawning at 2-age. The ages at major spawning groups were most 3-age, and they maximum GSI index was 14.91 (female), 8.96 (male) at 5-age, respectively.

• Journal of Animal Science and Technology
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• v.49 no.2
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• pp.195-202
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• 2007

The growth traits in swine are economically important, which are measured by gain in weight during test period or by age of days to certain weight. However, the difference in growth rate due to individual performance and also other factors occurs. The more reasonable estimation of the measurements of these traits provides the less error in genetic evaluation of pigs. The data from 1,576 heads being weighed periodically of Gyungnam-heugdon(Berkshire) were analyzed to estimate the growth curve which is used to decide average daily gain and days to 90kg. It may not be possible to directly compare accuracy between the conventional methods and the alternative methods. However, the alternative methods by growth curve would be superior to the conventional methods not only in theoretical background, but also in acceptability for diverse factors such as breed, sex and age. The theoretical superiority of the alternative methods comes from estimation at same age in daily gain and calculation of additional days from measuring date to days to 90kg by growth curve of individual. Also this can be easily adopted in a computer system according to breed and sex.

• Korean Journal of Community Nutrition
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• v.1 no.3
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• pp.405-422
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• 1996

The purpose of this study is provide reference data for anthropometry and body composition and also to compare body fat estimation among skinfold thickness, BIA and NIR methods. Anthropometric measurements of height, weight, eight sites of skinfolds and six sites of circumferences were taken from 76 elderly male and 153 elderly female. Skinfold thicknesses, body composition and circumferences except waist were lowered with advancing age in elderly females and males. The degree of change with age vaired among parameters but was consistently and significantly(p<0.05) greater in elderly females than I males. Although sum of skinfold thicknesses and the amount of central and peripheral fat were significantly higher in females than that of males, the ratio of central fat to peripheral fat was significantly greater in males than in females. WHR is also significantly higher in males than that of females. This indicates that fat distribution of males tend to be centralized toward the trunk of the body than females. Estimation of body fat from skinfold thickness(male : 18.5$\pm$4.1$\%$, female : 29.7$\pm$4.0$\%$) and BIA(male : 19.5$\pm$7.3$\%$, female : 29.6$\pm$6.7$\%$) were similar but were significantly different from NIR method(male : 24.7$\pm$5.6$\%$, 34.8$\pm$4.9$\%$). Estimation of body fat by NIR measurement seemed to be more overestimated. Understanding the normal changes in body composition with increasing old age, and the ability to measure these changes and compare them with appropriate reference data are important for the health of the elderly.

• Journal of Ecology and Environment
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• v.32 no.2
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• pp.109-113
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• 2009

Tree-ring width analysis has been used to assess the effects of air pollution on tree growth around industrial complexes. Our study was conducted to elucidate the effect of air pollutants on annual ring growth in black pines (Pinus thunbergii) of age 41$\sim$48 years around Ulsan Metropolitan City. The growth data were analyzed by multiple regression and the results are as follows: 1. The annual ring increment of black pines increased with tree age until age 40 years and then decreased gradually after age 40 years. 2. The increment of annual ring width of black pines was affected more by precipitation and evapotranspiration than air temperature. An annual ring decline appeared in the years 1968$\sim$1983, when annual ring indices below zero were observed. Decreased annual ring growth during this period may have been due to air pollution. 3. The heavy metal with the strongest effect on annual ring growth of black pines in the experimental stand was lead (Pb). The concentration of lead in the stand was estimated as over 6 ppm. 4. The technique of tree-ring width analysis may be useful for estimation of the extent of pollution in forest areas near industrial complexes.

• Journal of Korean Society of Steel Construction
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• v.25 no.4
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• pp.369-377
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• 2013

The age-adjusted effective modulus method has been known to provide more precise assessment than the traditional Yassumi method for long-term behavior estimation of prestressed composite girders. The age-adjusted effective modulus method, however, involves complicated calculation, thereby making the Yassumi method more prevalent in actual design. This study presents rational approaches to revise creep coefficients for the Yassumi method by using parametric study results obtained from the age-adjusted effective modulus method.